GPT-5.1 vs GPT-5.5

GPT-5.1 against GPT-5.5
GPT-5.1GPT-5.5
Coding index53.367.8
Benchmarks behind it Partial, 2 benchmarks Partial, 2 benchmarks
Output $/Mtok$10.00$30.00
Cost per solved task$1.02$1.65
Context window400K1.05M